The present invention relates to a building block for construction sets and especially to toy building blocks capable of joining with other similar blocks to form electrical circuits.
In U.S. Pat. No. 3,005,282 there is disclosed a building block in which a top face is provided on its one side with at least one row of coupling pins and on its other side with counter-coupling sockets for connection with the coupling pins of an adjacent similar building block. Such blocks are widely sold under the trade names "LEGO" and "DUPLO". It is furthermore known from Swiss Pat. No. 455,606 that at least some of the coupling pins may have electrically conducting surfaces or that the side of the face provided with counter-coupling sockets may have electrically conducting connectors intended to establish electrical contact with the conducting surfaces of an adjacent, coupled building block, when the two building blocks are coupled together mechanically.
These known building blocks for constructing electrical circuits are expensive to manufacture, cannot be used universally with other building blocks of the same building block system and require the user to have at least an elementary knowledge of electrotechnology with respect to circuit diagrams.
In German patent application No. 2,552,587, a clamping building block with possibilities for electrical connections is disclosed, in which an electrical connection is produced at the places of contact between elevations and depressions of the building block by connecting contact sites mounted at these places. In this system special attention has to be given to avoid a short circuit when connections are made. How the contacting sites are mounted is not explained in the patent.
It is an object of the present invention to provide a building block of the aforementioned type, having electrical contacting means.
A further object is to provide such a block in which the coupling pins and counter-coupling sockets may be combined at will with conventional blocks of the same block system which are provided without contacting means and the contact-making ability.
A still further object is to provide such a block capable of forming short-circuit-proof electrical connection between bipolar circuits.
The development of the building block of the present invention prevents short circuiting between the circuits associated with different row of coupling pins of two building blocks, when two similar building blocks are coupled together. This is so even when the blocks are perpendicular to each other. The blocks may thus be assembled without any special precautionary measures and without electrotechnical knowledge on the part of the user.